Brake-valve device



L. V. LEWIS BRAKE VALVE DEVICE April 14, 1925. 1,533,322

Filed Nov. 17. 1923 Lilli mill" .Hill l l 26 23 Z 2 INVENTOR ,l LLOYD V. LEWIS ATTORNEY Patented Api. 14,1925

UNITED sfr-Afri-:s j 153.1WENT- o I- 1,533,322l FFICE.

LLOYD v. LEWIS, or nnenwoon, PENNSYLVANIA, AssIeNoa :no 'ran wns'rmenonsn A1B anexa comm, or WILMEBDINQ, PENNSYLVANIA, A coaroaArIoN or PENNSYLVANIA.

BRAKE-vermi. navxcn I Application led November 17,1923. vSerial'l'lio. 675,249.

To all whom' 'it Imay condene.'

Be it known that I, LIoYD V. LEWIS, a citizen of the United States, residingat Edgewood in the county of Alleghen and` State of` ennsy1vania,have invente new and .useful Improvements in Brake-Valve Devices, 'of which the following is a speci-v iication.

This invention relates to brakev valve de-l' vices, and more particularly to the type 1n which the fluid pressure is regulated according to the degree of compression of a spring.

The principal object of my invention is to provide an improved brake valve device of the above chanacter. a

In the accomp ying drawing Fig. 1( is a central sectional view of a bralie valve device constructed in accordance wlth my mven- ,tion; Fig. 2 an inverted plan view of the;

regulating cam; Fig. 3 a side elevation of ated sleeve; Fig.- 7 a plan view of the'sleeve I shown in Fig. 6; Fig. 8 a planview of the valve operating plate; Fig, 9 a section on the'y line 9 9 of Fig. 1; and Fig.10 aplanl view of the Lsupply valve stem bushing.

As shown inthedrawing, the brake valve device may comprise la casing 1 having a! shouldered annular cavity for receiving a diaphragm 2. The diaphragm 2. is secured in position by a ring 3 which 1s clamped against the^ diaphragm by a cover or capv member 4 having screw-threaded engagement in the casing 1. y Bushings 5 and 6 are lscrewed into threaded openings" at theunder face of the casing 1 and mounted iii the bushing 5 is an exhaust valve and stem 7 adapted 'to en age a valve seat provided in a fitting 8 whic -1s screwed into the lower end of the bushing 5. I

lThe valve 7 is provided with a collar 9 adapted to engage the under face of a iiange or'medat the upper end-of bushing 5.

-Interposed' between the fitting 8 and the collar 9 is a coil spring 11.

Mounted in the bushing 6 is a supply valve operating stem' 12 having its lower '13 which has screw-threaded engagement inend extending into a central bore of a fitting th'e lower end of bushing 6.) The valve stem 12 is provided with a collar14 adaptedto -afd extendin engage theunder face of a flange 15 formed at the upper end of bushing 6. Interposed between the fitting 13 and the collar 14 is a colll spring 16. ,1 The fitting' 13 is provided with a valve chamber 17 containing a supply valve 18 having a stem 19 adapted to engage -m a central bore of the valve operatin stem 12.

. Engaging the upperpends of t e stem 7 and the valve operating stem 12 is a plate 20 havlng a central concave depression in which the'ball shaped end of a diaphragm l member 214 engages.

Secured Within an annular cavityv in the cap member 4 is a ring Shaped cam member -22 provided on its under face with two simidiaphragm 2 and secured tolthe cam ring 22 isa air of oppositely arranged flat sprin each adapted to engagea correspon ingwing 26 when the sleeve 24is vin .its release posltion.

At the releasel end of@ each cam face 23 the cam ring 22 is provided with a pocket adapted to receive the corresponding wing 26, so that, as shown in Fig. 4, rotative movement of the ring 22 from release' position, will first cause a quick axial movement of the Wings 26 until said win s have been yforced to a position in which t eir inclined :facesy engage thel cam faces 23. Y

In operation, when the handle 25 is in releaseposition, the wings 26 of the sleeve 24'engage in the corresponding ockets of the cam .ring 22. If it is desire to apply the brakes, the handle 25 is operated to rotate the sleeve 24. The initial rotative movement iirst causes the wings 26 to ride out ofthe pockets in the cam ring to thereby effect-A a downward movement of the sleeve 24f-and thus by, acting on the upper end of the spring 27, said spring is initially compressed to a certain extentwith a slight rotative movement of the handle 25.

, Itmay bestated that the notch or pocket in the cam ring 22 provides an imposiive lock tending to retain the brake valve handle in release position and at the same time provide a-wide opening of the exhaust valve 7 in release position, which can be taken up so as to close the exhaust valve by a. short preliminary movement of thehandle required to move the wings 26 fromthe notch to the elevation of the cam surfaces 23; rendering the major portion of the stroke available for graduating the application of the brakes.

Further movement of the handle causes a more gradual axially downward movement of the sleeve 24, through the engagement of the wings 26 with the cam' faces 23, and a corresponding further compression ofI the spring 27.

Since the spring 27 acts on the diaphragm 2, said diaphragm will be depressed or moved downwardly by the ressure of the,

spring. Preferably the sprlng 16 is some#y what lighter than the spring 11, so that the initipl movement of the plate 20 by tihe diaphragm 2 operates, with the stem 7 acting as a fulcrum, to move the stem 12 until the lost motion between the stem v 12 and the valve stem 19, is taken up. Then further movement of the stem 12 is resisted by both springs 16 and 32 and since the combinedresistance of the springs 16 and 32 exceeds the resistance of sp-ring 11, the plate 20 will now move, with the stem 12 acting as a fulcrum, about the pivot pin 21, so than said plate is 'rocked on the pivot pin 21 to depress the steml 7. The exhaust valve associated with stem 7 then moves to litsseat.- Further movement of diaphragm 2 then rocks the plate 20 with the stem 7 lacting as a fulcrum, so as to operate stem`12 to open the supply valve 18. v

Fluid under pressure is then supplied from valve chamber 17, which is connected by pipe 29 to a source of fluid under pres-- sure, to diaphragm chamber4 30. VSaid chamber is connected by pipe 31 to the brake cylinder or brake chamber, so that fluid undervr pressure is supplied thereto, to effect an ape plication of the brakes. When the pressure in chamber y 30 acting on diaphragm 2 slightly exceeds the opposing pressure of thespring 27 the diaphragm will be moved upwardly, so as to permit the valve 18 to be closed by the spring 32, since the combined pressures of the s rings' 16 and 32 will act on the plate 20, during the upward movement of said plate, so as to tilt the plate, with the stem 7 acting as a fulcrum and the member 21 acting` as a pivot.

lt will now be seen that both the su ply ,valve 18 and the exhaust valve 7 are cllised or lapped and the parts will remain in this position, so long as the pressure inthe brake cylinder corresponds with the pressure toA lease position, so that a reduction in the com-v pressionof spring 27 is effected. This reduction in spring pressure on diaphragm 2 causes the higher brake cylinder pressure on the opposite side of the diaphragm to move the diaphragm upwardly, permitting the plate 20 to be .tilted upwardly by the action of the spring 11 on the exhaust valve 7, lwith stem 12 acting as a fulcrum for said plate, thus permitting the exhaust valve to be unseated by the spring 11.y Fluid under pressure in the brake cylinder will then be vented from the chamber 30 and the brake cylinder .to the atmosphere, so as to deffect the release of the brakes.

been increased to correspond with the increased pressure of spring 27, the valve 18 will be again closed, inthe manner hereinbefore described.

lf leakage from the bra-ke cylinder should Y occur while the handle 25-is in a given brake applying position, the reduced pressure of the brake cylinder in chamber 30 acting on diaphragm 2 will permit the spring 27 to operate the diaphragm 2, so as to open the supply valve 18 and admit 'luid to the brake cylinder to compensate for'the leakage.

When the handle 25 is in release position, the spring 27 is not under compression, and in order to hold the sleeve 24 and handle 25 against possible vibratory movement, the springs 28 are provided, said springs being adapted in release position, to bear against the wings 2 6 and thus hold the sleeve 24 in position by the engagement of the wings 26 in the pockets of the cam wing 22.

The exhaust valve 7 and the supply valve stem 12 being in non-rigid engagement with plate 20, there will be no forces acting on- -of the exhaust valve, of means operated by said abutment for first seating the exhaust valve while the supply valve 1s seated and for then unseating' the supply valve while the exhaust valve remains seated.

2. In a fluid pressure controlling valve device, the combination with a movable abutment, a normally open exhaust valve,

and a v normally closed supply valve, ot'4 means engaging said valves and 'movable by said abutmentrelatively to said supply valvey for closing the exhaust valve and then movable vrelativel to the exhaust valve for opening the supp y valve.

In a fluid pressure controlling valve device, the combination with a movable abutment, a normally open exhaust valve, and a normally closed supply valve, of a `spring or opposing the closing of the exfor operating the exhaust valve upon move said diaphragm ment of said abutment and the exhaust valve acting as a fulcrum for said member for operating said supply valve upon a further movement of said abutment.

A5. In a fluid pressure controlling valve device, the combination with a flexible diaphragm, an adjustable spring acting on said diaphragm, .an exhaust valve anda fluid supply valve, of a member engaging said valves and movable by said diaphragmupon compression of said spring and relatively to said supply valve for closing said exhaust valve and then relatively to'wsaid exhaust valve for opening said supply valve.

6. In a fluid pressure controllin valvfe device, the combination with a flexi le diaphragm and lvalve means operated by said diaphragmi-for controlling the supply of fluid under pressure, of a spring acting on a rotatable Asleeve containing said sprin a member having a cani face, and an e ement associated with'said sleeve andengaging said cam face and operable b movement on said face upon rotav tion o said sleeve for moving said sleeve to compress said spring. 7 v

7. In a fluid ressure controlling valve device, the combination with a casing, of a removable bushing secured infsaid casing, an

exhaust valve operatingl stem `contained in said bushing, a spring in said bushin acting on said valve stem, a second removab e bushphragm and means operated by said' d'ia- Y phragm for controlling the supply of fluid under pressure, of a spring acting on said diaphragm and means for varying the compression of said spring comprising a rotatable membr engaging said spring, a cam device having a cam face adapted to`be engaged by said member for gradually compressing said spring upon rotation of said member, vand means for effecting a quick movement of said member and a sudden compression of said spring in advance of the engagement of said member with said cam face.

9. In a fluid pressure controlling valve device, the combination with a flexible diaphragm and means operated by said diaphragm for controlling the supply of fluid under pressure, of a spring acting on said diaphragm and mea'ns for varying the compression of said spring comprising a rotatable member engaging said spring, and a cam mechanisn for first moving said member to rapidly compress' said spring upon a small rotative movement of said member and for then gradually moving said member.' to gradually compress said spring upon a further rotative movement of said member.

.10. In a fluid pressure controlling valve device, the combination with a flexible diaphragm and means operated by said -diaphragm for controlling the supply of fluid under pressure, of a spring actlng on saiddiaphragm and means for varying the compression of said spring comprising a rotatable member' engaging said spring, a lug associated withpsaid member, a cam device having a cam -face adapted to be engaged by said lug upon rotative movement of said member, said cam device being provided with a recess adjacent to said cam face and in which said lug engages in the normal position of said member.

In testimony whereof I have hereunto set my hand.

LLoYn v. LEWIS. 

